GH4169镍基高温合金薄壁钻削过程中的应力及变形研究

利用ABAQUS有限元仿真软件建立了镍基高温合金GH4169薄壁件钻削模型,分析钻削GH4169薄壁件过程中的薄壁变形和应力变化。根据钻削过程中钻头下方工件材料的应力及变形特点将其钻削过程分为5个阶段:第1阶段,工件变形以整体弹性下凹变形为主,并在钻头横刃旋转接触圆形区域下方发生了局部塑性形变;第2阶段,在制孔区以塑性变形为主,在非制孔区弹性变形量大于塑性变形量;第3、第4、第5阶段工件变形相差不大,在孔口边缘形成了较大的材料外翻,其余部分形成了一定的塑性变形。在钻头横刃刚与薄壁件接触时,钻头横刃与薄壁件接触部分表现为应力集中;随着钻头的向下进给,钻头后刀面与薄壁件呈面接触,应力波开始以大致为圆形的波形扩散在薄壁件上,随后以近似方形传递到薄壁件四边。

Research on Stress and Deformation in the Process of Drilling Ni-based Superalloy Thin walled Workpiece

ABAQUS finite element simulation software was used to establish the drilling model of GH4169 thin walled Ni-base superalloy.According to the stress and deformation characteristics of the workpiece material under the drill bit in the drilling process, the drilling process is divided into five stages. In the first stage, the deformation of the workpiece is mainly overall elastic concave deformation, and local plastic deformation occurs under the rotary contact circular area of the drill bit.In the second stage, plastic deformation is mainly in the bit action area, while elastic deformation is larger than the plastic deformation in the bit non action area.At the third, fourth and fifth stages, the deformation of the workpiece is not different, and a large material eversion is formed at the edge of the orifice, while the rest of the workpiece is formed a certain plastic deformation.When the bit blade is in contact with the thin walled part, the contact part between the bit blade and the thin walled part shows stress concentration.With the downward feed of the drill bit, the back cutter surface of the drill bit is in contact with the thin walled part, and the stress wave begins to spread on the thin walled part in a roughly circular waveform, and then passes to the four sides of the thin walled part in an approximate square.